40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
 List  |  Find  |  Login  |  Help 
Entry  Fri Dec 14 03:32:51 2012, Ayaka, Update, LSC, High frequency noise in AS signal XARM_OL.pdfAS_ITMXexc.pdfASspe_noise.pdfASgain.pngASspe.tar.gz
    Reply  Fri Dec 14 09:31:59 2012, rana, Update, LSC, High frequency noise in AS signal 
       Reply  Fri Dec 14 10:09:30 2012, Ayaka, Update, LSC, High frequency noise in AS signal 
Message ID: 7832     Entry time: Fri Dec 14 09:31:59 2012     In reply to: 7829     Reply to this: 7833
Author: rana 
Type: Update 
Category: LSC 
Subject: High frequency noise in AS signal 

This is NOT calibrated. Its sort of calibrated in the 500-1000 Hz area, but does not correctly use the loop TF or the cavity pole.

As for the noise, remember that the whole point of changing the AS whitening gain was to turn on the whitening filter AFTER locking. With the WF OFF, there's no way that you can surpass the ADC noise limit.

Quote:

I calibrated the AS error signal into the displacement of the YARM cavity in the same way as I did before (elog).

ELOG V3.1.3-